Spring device

ABSTRACT

A spring device arrangement in particular for the area of railway vehicles, in particular for spring suspension between a bogie and coach body, in which a spring device is located between a supporting plate and a substructure includes two spring systems connected in parallel. Each spring system comprises three parallel springs, the spring being an air spring or hydropneumatic spring comprising a bellows of elastomer material which connects the supporting plate to the upper part of a spring-support piston, the springs of the spring system being interconnected in a pressure-equalizing manner by an overflow duct. The spring is disposed outside the spring and extends from the supporting plate to the substructure, and the spring is installed in the support piston of the spring, a force-transmitting pressure piston simultaneously being used. The lower part of the pressure piston rests on the spring and its upper part, which is provided with an end stop, projects into the interior of the spring, the pressure piston having inside the region of contact with the support piston a vertical slide surface and a stepped stop which produces pretension in conjunction with the spring.

BACKGROUND OF THE INVENTION

1. Field OF the Invention

The invention relates to a spring device particularly in the sector ofrail-borne vehicles, and there especially for spring suspension betweena bogie and a coach body. The spring device is arranged between asupporting plate and a substructure and consists of two spring systems Iand II connected in parallel. Each spring system comprises three springsarranged parallel to each other, namely a first spring A, a secondspring B and a third spring C. Such a spring device is known from DE 3412 547.

2. The Prior Art

In order to assure safety against derailment with a spring deviceaccording to DE 34 12 547 as well as with other known spring devices(DE-B-11 90 811; DE-B-20 60 960; DE-B-24 40 069; DE-C-44 04 878;FR-A-812 045; JP-A-4/29631) also in emergency operations, costlyadditional bogie constructions were required in the coach bodyheretofore in most cases, or a larger installation space is needed forthe spring device. The greatest problems arise in this connection of arelatively long and torsion-resistant coach body tube has to be takeninto account, and proof of safety against detailing has to be furnishedfor emergency operations.

Now, based on said state of the art the problem of the invention is toimprove the safety against derailment in emergency operations whileavoiding complicated and cost-intensive coach body constructions, i.e.,to improve such safety in the twisting platform in the event of failureof the spring devices known until now.

SUMMARY OF THE INVENTION

This problem is solved by a spring device according to thecharacteristics of patent claim 1, i.e. by using springs A, B and Cdescribed below in more detail.

First spring A

Spring A is an air or hydropneumatic spring comprising a bellows made ofelastomeric material (i.e., rubber or rubber-like plastic), which, withsecuring means, connects the supporting plate with the upper part of aroll-off piston.

Springs A of the two parallel connected spring systems I and II areconnected with each other in a pressure-equalizing manner by means of anoverflow duct, whereby the overflow duct extends in particular withinthe supporting plate and is connected with a valve, which is arrangedbetween the two spring systems.

The supporting plate is advantageously provided within spring A with astop with an integrated inlet opening.

Second spring B

Spring B, which in particular has the form of a spiral spring made ofsteel or elastomeric material, is arranged outside of spring A andextends from the supporting plate up to the substructure.

Third spring C

Spring C also has in particular the form of a spiral spring made ofsteel or elastomeric material and is installed within the roll-offpiston of spring A, using at the same time a pressure piston fortransmitting force, said pressure piston resting with its lower part onspring C particularly in connection with a flange-like widening, andprojecting with its upper part, the latter being provided with aface-like stop, into the interior of spring A, whereby the pressurepiston has a vertical slide surface within the area of contact with theroll-off piston, as well as a step-like stop, which in conjunction withspring C produces pretension.

The face-like stop of the pressure piston is advantageously designed inthe form of a plate particularly in connection with a plastic layer.Said stop is mounted directly opposite the supporting plate.

The substructure of the spring device is usefully equipped withadditional springs particularly in the form of elastomer springs ormetal/elastomer-layered springs, whereby the substructure advantageouslyconsists of a top plate and a bottom plate, with the springs beingarranged between said plates.

The two parallel connected spring systems I and II are fully arrangedwith the same height.

BRIEF DESCRIPTION OF THE DRAWING

The invention is now explained with the help of an exemplifiedembodiment and by reference to a schematic drawing depicting anembodiment of the spring device arrangement according to the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The two spring systems I and II, which are connected in parallel andhave the same height and which are disposed below supporting plate 1,each consist of a spring A and a spring B, said springs being arrangedparallel with each other as well. Spring A is an air spring or ahydropneumatic spring comprising a bellows made of elastomeric material,and a roll-off piston 3, whereas spring B is a spiral spring made ofsteel or elastomeric material, whereby spring A is located within springB. An overflow duct 5 with a valve 10 connects the two springs A in apressure-equalizing manner, whereby the overflow duct extends withinsupporting plate 1.

Now, spring A serves for automatically controlling the height of thefloor of a vehicle and keeps such height constant under all loadconditions. Spring B is load/travel-dependent. The difference in loadbetween the empty and the loaded vehicle is absorbed only by spring A inthe normal case, with the share in load of spring B remaining the sameunder any load conditions.

Depending on the design of springs A and B it is possible that theimmersion frequency between empty and full loads remains constant to thehighest possible degree.

Now, if spring A is defective (e.g. due to loss of pressure), spring Bwill assume the emergency operation propoerties. With empty loads,spring B Lakes over the share in load of spring A.

Furthermore, spring systems I and II are equipped with an additionalspring C, which is connected parallel with springs A and B as well anduses at the same time a pressure piston 6 for transmitting force. Thelower part 6' of the pressure piston is provided with a flange-likewidening 13, which rests on spring C. The upper part 6" of the pressurepiston is provided with a face-like stop 7, which is designed in theform of a plate and equipped with an additional plastic layer 7', andwhich projects into the interior of spring A. Stop 7 of pressure piston6 is arranged directly opposite stop 12 of supporting plate 1, wherebystop 12 is provided with an integrated inlet opening 11. Furthermore,pressure piston 6 has a vertical slide surface 8 within the area ofcontact with roll-off piston 3, as well as a step-like stop 9, whichproduces pretension in conjunction with spring C.

Now, in the event of failure of spring A (emergency operation), spring Csupports spring B especially under full-load conditions and provides fora progressive spring characteristic. Spring C is not active under normaloperating conditions (when spring A is intact), disregarding exceptionalcases.

Substructure 4 is advantageously equipped with additional springs 14,for example in the form of rubber springs or metal-and-rubber layeredsprings. Here the substructure consists of a top plate 4' and a bottomplate 4", with springs 14 being arranged between said plates.

If an air spring is used, it is advantageous, furthermore, if at leastone passage opening 15 is present within the upper part 6" of pressurepiston 6 particularly in the lateral zone of the latter, such passageopening connecting the interior of spring A with the interior ofroll-off piston 3.

What is claimed is:
 1. A spring device arrangement comprising a supporting plate, a substructure and a spring device located between the supporting plate and the substructure, said spring device consisting of two spring systems connected in parallel, each spring system in turn comprising three springs arranged parallel to each other, namely a first spring, a second spring and a third spring, characterized in thatthe first spring is an air spring comprising a bellows made of elastomeric material and connecting the supporting plate with the upper part of a roll-off piston by utilizing securing means, the first springs of the spring systems being connected with each other in a pressure-compensating manner by means of an overflow duct; the second spring is mounted outside the first spring and extends from the supporting plate to the substructure; and the third spring is installed within the roll-off piston of the first spring, simultaneously using a pressure piston for transmitting force, said pressure piston resting with its lower part on the third spring and projecting with its upper part, which is provided with an end stop, into the interior of the first spring, the pressure piston having inside the region of contact with the roll-off piston a vertical slide surface as well as a stepped stop which produces a pretension in conjunction with the third spring, the upper part of the pressure piston having at least one passage opening connecting the interior of the first spring with the interior of the roll-off piston, and said substructure comprises a top plate and a bottom plate and is equipped with additional springs arrangement between said top and bottom plates.
 2. The spring device arrangement according to claim 1, characterized in that the overflow duct (5) extends within the supporting plate (1).
 3. The spring device arrangement according to claim 1, characterized in that the overflow duct (5) is connected with a valve (10), the latter being arranged between the two spring systems (I, II).
 4. The spring device arrangement according to claim 1, characterized in that the first spring has an inlet opening arranged directly above the pressure piston in the axial direction of said pressure piston.
 5. The spring device arrangement according to claim 1, characterized in that the end stop of the pressure piston is designed in the form of a plate.
 6. The spring device arrangement according to claim 1, characterized in that the end stop of the pressure piston is provided with a plastic layer.
 7. The spring device arrangement according to claim 1, characterized in that the supporting plate is provided within first spring with a stop, said stop being arranged directly opposite the end stop of the pressure piston.
 8. The spring device arrangement according to claim 1, characterized in that the lower part of the pressure piston widens to form a flange, said flange resting on the third spring.
 9. The spring device arrangement according to claim 1, characterized in that the second and third springs are steel spiral springs or elastomer springs.
 10. The spring device arrangement according to claim 1, characterized in that the parallel connected ring systems (I, II) are arranged with the same height.
 11. The spring device arrangement according to claim 1, wherein the spring device is located between a bogie and a coach body in a rail-borne vehicle.
 12. The spring device arrangement according to claim 1 wherein said additional springs are elastomeric springs or metal elastomeric layer springs.
 13. The spring device arrangement according to claim 1 wherein said passage opening is present in a lateral zone of the pressure piston. 